Currently the existing skin dilator is usually composed of an expander made of silicone material, an injection tube and an injection port. The injection tube is connected to the expander and the injection port. The expander is a sealed elastic bag that can be expanded several times. Two methods are adopted in use; one method is outside injection port method: to embed the expander to the subcutaneous tissue and the injection port and partial injection tube are outside of the body surface; and the other method is inside injection port method: to simultaneously embed the injection port and the injection tube to the subcutaneous tissue. By periodically injecting normal saline water through the injection port which reaches the subcutaneous expander via the injection tube, the expander is gradually expanding to dilate the skin, to form the expanded flap to repair the tissue defects on the body surface. The whole process takes 3-6 months.
At present, some complications may occur for the clinically used skin dilators during the treatment (about 20%-40% according to reports), such as local skin thinning, necrosis after the expansion of the embedded dilator after surgery, and sometimes even skin rupture in the expanding part, causing treatment failure and great losses to the patients and medical staffs.